A friend of mine has a Hanger 9 Pulse XT PNP that came with the Evolution 46 in it. It runs good in level flight, and when testing it on the ground, we can run the engine and hold the plane vertical and no problem. But while flying, if we loop the plane it quits. So are we too rich, too lean, or is there another problem?

Thanks

The first thing I would check is the tank and clunk.

Try the same test you did, but do it with a half-full tank. If it continues to run while held vertically, try continuing to rotate it to inverted (Easy to do if you put a person on each wingtip).

Could be the clunk is stuck at the bottom, or you have a split somewhere in the clunk line.

Thank you, I'll let you know if it didn't help or find any problem.

I would look at the mixture of the fuel may b its a birt too lean

I think Minn has this one.... I bet the clunk line is too long not allowing the clunk to fall to the fuel

I would bet on a combination of the tank being lower than the carb and a slightly lean setting.